How to control GPIOs on Pin-Header 2?

i’m using RockPiS (hardware v12) and i can control GPIOs on PinHeader 1 without problems using libmraa. Works great.
But i can’t control GPIOs, e.g. GPIO 77 up to 80 (pin 2,4,6,8 on PinHeader 2). I need these GPIOs, too. Can you help?
Many Thanks.

Currently it is not available to control GPIOs on 26-pin Header 2 by using libmraa.

Okay. I understand.
And when i try to use the filesystem like …

cd /sys/class/gpio
sudo echo 78 > export
cd gpio78
sudo chmod 666 /sys/class/gpio/gpio78/direction
sudo echo out > direction
sudo chmod 666 /sys/class/gpio/gpio78/value
sudo echo 1 > value # output high
sudo echo 0 > value # output low

… it has no effect on the Pin4 at Header2, too.
Is there no chance to use GPIOs from Header2?
Thank you.

You can try this. At first, change to superuser, and then use command echo to set direction and value.

For example,

$ sudo su
# echo 78 > /sys/class/gpio/export
# echo out >  /sys/class/gpio/gpio78/direction
# echo 1 > /sys/class/gpio/gpio78/value
# echo 0 > /sys/class/gpio/gpio78/value

the best solution is to use a port-expander (i use a SX1509 with I²C).
That’s working great.